The Joint Photographic Experts Committee (JPEG) has created different standards for compression of still images. The initial JPEG standard used discrete cosine transform compression. A newer version of JPEG, JPEG2000 also referred to as JPEG2K, relies upon a wavelet-based method. JPEG2K encoders encode the digital image data in accordance with this standard, compressing the file size for storage and/or transmission, and JPEG2K decoder can decode them prior to display or printing.
The JPEG2K codes streams may contain regions of interest that offer several mechanisms to support spatial random access or access at varying degrees of granularity, or resolution. This allows the decoder to adjust the level of resolution depending upon the quality of the image. The main visual artifact that reduces image quality in JPEG2K image is blur, which results from a loss of detail, mostly at the edges of objects in the image. Excessive low pass filtering typically causes the blur.
Image quality measures may take many forms, including Perceptual Visual Quality or PVQ. To maintain visual quality, it becomes important to quantify the numbers of artifacts introduces by the compression process.